Layered LiMnxCoyO2 was prepared by co-precipitation preparation of precursor,and then sintered under 900 ℃ with different time.The results of X-ray diffraction (XRD),scanning electron microscopy (SEM) and transmission electron microscopy (TEM) show that the crystalline structure of the layered LiMnxCoyO2 is rhombohedron lattice whose space group is R(3)m,and has a similar lattice constant with LiCoO2.Under different sintering time,samples are spherical under scanning electron microscopy (SEM);as the sintering time extended,spherical morphology is better.With different samples of electrochemical performance test show that the samples with longer sintering time and higher relative content of Mn has better initial charge-discharge capacity and cycle performance.%通过共沉淀法制备前驱体,随后在900℃下经不同时长烧结得到了层状LiMnxCoyO2.X射线衍射、扫描电镜和透射电镜的研究结果表明,层状LiMnxCoyO2的晶体结构是菱面体点阵,空间群是R3m,点阵常数与LiCoO2非常接近.不同烧结时长下得到的样品在扫描电镜下均呈球状,随着烧结时间延长,球形规整度变得更好.对不同样品的电化学性能测试表明,烧结时间越长,样品中Mn的相对含量越高,其首次充放电比容量和循环性能越好.
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